Published on Pambazuka News, by Akinyi Margareta Ocholla, May 31, 2012.

Science shows that sexuality is formed beginning childhood. It is entirely possible one can grow up to be sexually attracted to persons of the same sex. If you think your brain is complex, you’re right – It is extremely complex. Just as every person has a special genetic coding, making her completely unique, so too does she have a brain that operates in a completely unique way – without exception.

Scientists who have studied human sexuality will tell you that it (and I venture to assume animal sexuality in general) is conditioned gradually over a period of time from early childhood – perhaps even from the time the foetus is in the mother’s womb. Again it’s important to understand that there is no absolute and complete explanation for the development of sexuality in its entirety – that is to say, our sexual orientation, our libido, our liking or disliking of different human voices, bodies, faces, scents, what we find kinky, sexy, exciting, emotionally and romantically satisfying, etc. Nor are there complete explanations for the fact that sexuality can tend to bend, flex and change with time. Because it’s true that human sexuality is fluid for many people. No one set of factors can possibly explain it all. At least most scientists have the honesty and humility to acknowledge this.

There have been many studies to find correlations between genes and sexual orientation, between types or concentrations of sex hormones and sexual orientation, between family-structure (i.e. mother and father, single-parent or same sex parents) and sexual orientation. These studies have found no significant or conclusive correlations. However what struck me as particularly interesting was a general explanation on the formation of sexuality in early childhood.

Three areas in the brain that begin wiring in early childhood are the Cochlea in the inner ear, the Hypothalamus – in particular the section called the INAH-3 and the Amygdala. Not only do they wire within themselves – they also wire and rewire between each other, to form a network that will transmit and interpret sounds. The cochlea is the part of the inner ear that is responsible for generating sound which is then transmitted to the brain. It captures the pitch of voices and sounds and transmits them to the hypothalamus. The INAH-3 in the Hypothalamus, in turn, is responsible for controlling physical aspects of sexual activity. Some studies have found that the INAH-3 is larger in gay men than it is in heterosexual men and women. The Amygdala is responsible for the emotional activities of a person, so feelings like fear, anger, excitement, happiness emanate from this part of the brain.

The pitch of the human voice is the analog (equivalent) of food when humans learn sexual behavior during childhood. The same way that the taste of different food creates representations of food that we want to eat or avoid so too do voices of speakers create in our brains the representation of sexual attraction targets. I suppose this is more or less the same thing that happens in animals (particularly mammals). The pitch of the voice serves as a detector of the sex of the speaker.

Based on this detection, the brain of the child builds representations of ‘man’ and ‘woman’. Through conditioning the child’s brain then uses these representations and builds mental models of who is sexually attractive and what activities cause sexual arousal. Therefore from early puberty or late childhood, a child’s hypothalamus’ INAH-3 or physical-sex-controller will be wired or tuned to respond to high and/or low-pitched voices. Those children whose physical-sex-controllers have been tuned to men will be attracted to men, and those who have been tuned to women will be attracted to women. Children who have been tuned to voices of both women and men in the same amount, will be sexually attracted to both women and men … //

… Thinking about my own likes, I would say that I’m attracted to low pitched voices of both women and men. But the low-pitched voice of a woman is still a slight notch higher than that of men in general, and I think somewhat closer to my own voice pitch (I wonder if perhaps my brain is generally tuned to resonate with sounds that are more like my own). Somehow my hypothalamus and amygdala have come to find that the mix of a low pitched female voice (with its resonance, choice of words – which also differ a lot from those of men, the pauses in a sentence, the emotional state that the female voice portrays during a conversation, etc) coupled with the image of the woman (her female physical attributes, her gait, face, her mannerisms, etc) is supremely sexy and attractive, in a way that a man’s cannot match.
(full text and references 1 to 7).